One of the more peculiar SI
measurement units, defined as 12/39.37 (approximately 0.304800609601) meter
s . One US Survey Foot = approximately 1.000002 feet.
As the name might suggest, the US Survey foot is used mostly by land surveyor
s in the United States
Most of the State Plane Coordinate System
s adopted by various states in the in the 1920
's through the 1950
's measure their coordinates in US Survey Feet. Because of a datum
change, most have these have been replaced by new systems defining coordinates in meters instead. However, some states allow the use of either unit.